CommandSet.OnMenuPaste - dragClient is always false

[chirndlerks]

.NET version

10.0.201

Did it work in .NET Framework?

Not tested/verified

Did it work in any of the earlier releases of .NET Core or .NET 5+?

Yes, 8.0.415

Issue description

We have migrated from .NET 8 to .NET 10.
I noticed that copying and pasting controls in the Forms Designer no longer works.
The problem seems to be that the dragClient boolean always remains false.

winforms/src/System.Windows.Forms.Design/src/System/Windows/Forms/Design/CommandSet.cs

Line 1905 in 065dd5f

bool dragClient = false;

From what I can tell, it's a bug from 5978f22

Either you set the boolean correctly

winforms/src/System.Windows.Forms.Design/src/System/Windows/Forms/Design/CommandSet.cs

Line 1918 in 065dd5f

designer = oleDragClient;

or change the if (dragClient) to if (designer != null)

winforms/src/System.Windows.Forms.Design/src/System/Windows/Forms/Design/CommandSet.cs

Line 1976 in 065dd5f

if (dragClient)

Steps to reproduce

A local build with ‘dragClient = true;’ on line 1925 fixes the bug.
I don't think an explicit example is necessary.

[LeafShi1]

@chirndlerks The Designer code in this repository does not affect actual design-time operations, so we cannot reproduce this problem. Under what circumstances did you encounter the issue of copy and paste not working?

[chirndlerks]

We host our own designer within our application.
We subsequently trigger the paste operation via our System.ComponentModel.Design.DesignSurface instance.
So this isn’t about the Forms Designer in Visual Studio, in case that was the assumption.

The code is called something like this:

var designSurface = new System.ComponentModel.Design.DesignSurface();
((IMenuCommandService)designSurface.GetService(typeof(IMenuCommandService))).GlobalInvoke(StandardCommands.Paste);

In general, I could write a sample application.
That’s very time-consuming, which why I was hoping I wouldn’t have to do that given the obvious bug.